<script setup>
	import {ref} from "vue"

    let sum = ref(1)
	let n = ref(1)

	function add() {
        console.log(n.value)
		sum.value += n.value
    }

    function sub() {
        console.log(n.value)
        sum.value -= n.value
    }
</script>

<template>
	<div>
		<h2>当前求和为 {{ sum }}</h2>
		<select v-model.number="n">
			<option value="1">1</option>
			<option value="2">2</option>
			<option value="3">3</option>
		</select> <br>
		<button @click="add">加</button>
		<button @click="sub">减</button>
	</div>
</template>

<style scoped>

</style>